Transformation Matrix Animation

• One way to support an animation capability: interpolate a transformation matrix.
• Keyframes would be ``poses'' of objects given by the animator.
• Functional animation would be applied independently to all entries of the transformation matrix.

Unfortunately, does not support animation of rigid bodies.

• Given two poses of an object that differ by a rotation.
• Under linear interpolation, object will not rotate but will turn inside out

  collapses to a plane in the middle of the interpolation.